Technical Field
This disclosure is related to high-pressure waterjet cutting systems and related methods, and, more particularly, to methods of cutting fiber reinforced polymer composite workpieces with a pure waterjet.
Description of the Related Art
Waterjet or abrasive waterjet cutting systems are used for cutting a wide variety of materials, including stone, glass, ceramics and metals. In a typical waterjet cutting system, high-pressure water flows through a cutting head having a nozzle which directs a cutting jet onto a workpiece. The system may draw or feed abrasive media into the high-pressure waterjet to form a high-pressure abrasive waterjet. The cutting head may then be controllably moved across the workpiece to cut the workpiece as desired, or the workpiece may be controllably moved beneath the waterjet or abrasive waterjet. Systems for generating high-pressure waterjets are currently available, such as, for example, the Mach 4™ five-axis waterjet cutting system manufactured by Flow International Corporation, the assignee of the present application. Other examples of waterjet cutting systems are shown and described in Flow's U.S. Pat. No. 5,643,058.
Abrasive waterjet cutting systems are advantageously used when cutting workpieces made of particularly hard materials, such as, for example, high-strength steel and fiber reinforced polymer composites to meet exacting standards; however, the use of abrasives introduces complexities and abrasive waterjet cutting systems can suffer from other drawbacks, including the need to contain and manage spent abrasives.
Other known options for cutting fiber reinforced polymer composites include machining (e.g., drilling, routing) such materials with carbide and diamond coated carbide cutting tools (e.g., drill bits, routers). Machining forces from such cutting tools, however, can promote workpiece failures such as delamination, fraying, splintering, fiber pullout, fiber fracture and/or matrix smearing. These types of cutting tools can also be susceptible to premature wear and must be replaced frequently when cutting fiber reinforced polymer composite workpieces to ensure an acceptable finish, thereby increasing operational costs. Moreover, machining fiber reinforced polymer composite parts with carbide cutting tools generates dust that can create environmental hazards and negatively impact machining performance.